CVE-2026-77357 (GCVE-0-2026-77357)

Vulnerability from cvelistv5 – Published: 2026-08-25 20:40 – Updated: 2026-08-25 20:40
VLAI
Title
Mesop: DoS in /hot-reload endpoint allows unauthenticated attacker to exhaust worker threads and crash the server
Summary
Mesop is a Python-based UI framework that allows users to build web applications. Prior to 1.3.3, applications running in debug mode expose a GET /hot-reload endpoint whose unbounded loop depends on the user-supplied counter parameter, allowing an unauthenticated attacker to hold worker threads with high counter values until the worker pool is exhausted and the server becomes unavailable. A single unauthenticated attacker can crash the Mesop server with minimal effort. Because the attack leverages worker exhaustion, the server remains unresponsive until it is manually restarted. This issue is fixed in version 1.3.3.
Severity
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CWE
  • CWE-400 - Uncontrolled Resource Consumption
  • CWE-834 - Excessive Iteration
Assigner
References
Impacted products
Vendor Product Version CPE status
mesop-dev mesop Affected: < 1.3.3
guessed Create a notification for this product.
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          "vendor": "mesop-dev",
          "versions": [
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        }
      ],
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            "subConfidentialityImpact": "NONE",
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          }
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              "description": "CWE-400: Uncontrolled Resource Consumption",
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        },
        {
          "descriptions": [
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              "description": "CWE-834: Excessive Iteration",
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              "type": "CWE"
            }
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      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-25T20:40:39.711Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
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          "name": "https://github.com/mesop-dev/mesop/security/advisories/GHSA-8p72-497j-83mx",
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          "url": "https://github.com/mesop-dev/mesop/security/advisories/GHSA-8p72-497j-83mx"
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        },
        {
          "name": "https://github.com/mesop-dev/mesop/releases/tag/v1.3.3",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/mesop-dev/mesop/releases/tag/v1.3.3"
        }
      ],
      "source": {
        "advisory": "GHSA-8p72-497j-83mx",
        "discovery": "UNKNOWN"
      },
      "title": "Mesop: DoS in /hot-reload endpoint allows unauthenticated attacker to exhaust worker threads and crash the server"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-77357",
    "datePublished": "2026-08-25T20:40:39.711Z",
    "dateReserved": "2026-08-20T19:28:35.245Z",
    "dateUpdated": "2026-08-25T20:40:39.711Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
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  }
}



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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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